This night collar from Red Dingo is the business, a bright halo tube that glows brilliantly in the dark. Waterproof for swimming, weatherproof and lightweight this collar can be trimmed to size then slipped over your dogs head for a perfect fit.
Available in green or red and two sizes:
Small/Medium to fit necks from 15cm-50cm
Medium/Large to fit necks up from 15cm-80cm.
It runs on one AAA battery.